Sheet for making cushion disks and method of making same



Aug. 1s, 1925. 1,550,086

C. E. MCMANUS SHEET FOR MAKING CUSHION DISKs AND METHOD 0F MAKING SAMEFiled Aug. 29. 1.923

f VAK? llatentecl, ,dans ld, ldlflo CHRLES E. Tillolllldlil'US, till?NEW YORK, lll'. Y.

SHEET iOlt MAKEN@ USHON DENK@ AND METHD OE MAKEN@ SAME.

application tiled August 29, lt. Serial No. 659,@95., s

-, a citizen of the United States, residing at lll the borough ofManhattan, city, county,

and Stateof NewYork, have invented certain new and useful lmprovementsin Sheets for Making Cushion lDisks and Methods of Making Same, of whichthe following is a specification, reference being made therein to theaccompanying drawings, which form a part thereof.

` My invention relates to a sheet of elastic, substantiallynon-absorbent material composed mainly of cork, which sheet has athickness which will permit cork disks to be cut therefrom to be used inclosure caps for sealing bottles, and to the method of producing same.

lit has long been the practice in the manufacture of bottle closures .ofthe crimped metal shell, as well as othertypes to use cushion disksformed either of natural cork wood, or V4'of composition cork,j amaterial formed of granulated cork wastethe granules of which have beenthinly coated with an adhesive or cement before being compacted andbonded to forrn a homogeneous i' product.

Because of the extreme care recpiinedv inv selecting the natural corkdisks in order to avoid the vpresence of pores of sucient magnitude tocause what is known as leakers due to passages at the lip of the bottle,even whenl a cap containing a dik is applied thereto withconsiderablepre sure; the da mand for composition" cork disks is pro- `seressivelyincreasing so at the present time,

' it is possibly greaterthanthat for the nat- .ttl

lto

ural cork. 'lhis may be attributed to the fact that composition cork ispractically lacking in 4voids corresponding with the pores of thenatural cork, possesses relativel higher elasticity and is. ofsubstantially unl- A form density and elasticity throughout. ,'lhecomposition cork disks have the disadvanf tage however, of having lessdurability than `the natural cork disk, owing to the tendency of thecork 'composition to soften when subjlected to the action of liquids fora prolonged period and of having a darker color than the natural corkand a tendency to dis.

color more rapidly than same.

llhile such characterlstics are present rn composition cork, the life ofa disk made therefrom is sucient to permit its use with many beverages,although, with certain beverages 1t has been found necessary to applyfacing disks of metal, foil, parchment paper or othermaterials, to thecentres of the disk in a position where the material of the disk will beprotected from contact with the bot- 'tles contents, the seal however,being made directly against the cork composition, and not against thefacing disk.

However, such faced disks require the application of the facingmaterial, centrally of the disks with care and accuracy so as to exposethe composition cork about the same ,in a position where it will seatagainst the lip of thebottle, and yet not be exposed to contact with theliquid within the bottle.

By my present invention, l am enabled to provide a sheet for makingcushion disks,

v corkn ln referring to cork of different grades, l halte reference notonly to the age at which the cork is harvested, but to the differentportions of cork, irrespective of its age. 'lhe ideal ageof corkfor usein bottle caps is from sin to eight years but generally at this periodonly one half of the thickness of the cork can beadvantageously used,owing to the fact that the libres at diderent stages of the developmentof the cork in process of growth develops pores of progressively in-4creasedmagnitude toward the outer bark.

'lhis .outer bark of itself, is so hard, brittle, and irregular as to bepractically a waste product. 'lhe inner laminations of the cork aresubstantially Vfree from pores of a depth which will interfere with theuse of this portion ofthe cork in making cushion disks.

ylhe portion of the cork bark adjacent the outer bark has large deeppores therein so that if it lle used for cushion disks in bottle caps,the deformation of the disk whenl the cap is applied to a bottle willordinarily be insuhcient to close such pores and thus form a perfectseal even when the cork is cut into sheets of one tenth of an inch inthickness. If the cork is cut into thinner sheets most of these sheetswill have fairly large openings extending entirely therethrough. Forthis reason this particular grade of cork is not adapted nor suitable,for use under conditions requiring thin cork substantially free fromlarge surface voids or openings extending entirely therethrough.

By my invention, however, this corkmay be effectively used in thinsheets as a sur facing for composition cork sheets since the magnitudeof the openings will permit them pacting same,

to be filled orclosed by a composition cork. backing thus presenting acontinuous smooth surface freefrom voids of a depth which will exceedthose in the surface-of cork of higher grades. The thinness of thesheets of natural cork will ensure all such voids passing entirelytherethrough.

It will readily be understood that the number and size of such openingsis not great, and that the plasticity of the composition cork, and thepressure used in comwill cause all such openings number or size to beeffec# tively filled. Furthermore, the surface of the sheet in allcases, is formed mainly of impermeable natural cork,` the small,isolated areas of composition cork being almost indistinguishable fromthe natural cork. if one of the composition cork fills, should come incontact with the neck of a bottle, it would form a perfect seat beingflush with the natural cork surface, would leave no crack or passage atthe point. If such a fill should occur in a position where itwill beexposed to the contents of irrespective of a bottle the exposed areawill not be suffi-1 cient to permit any material decomposition. of themass of composition cork backing, or suclh a distortion thereof as willaffect the sea Discolo'ration of such areas will notfbe objectionablebecause the small areas in each disk are ordinarily few in number andnot particularly noticeable.

The invention consists primarily kin a sheet for making cushion disksconsisting of a surfacing sheet of natural cork having voids extendingtherethrough, a stratum of composition cork, having portions thereofextending through and lilling said voids and having their exposedsurfaces substantiall flush with the adjacent surface of said7 naturalcork sheet, and an adhesive connectin said surfacing sheet to saidstratum; and 1n such other novel characteristics and in the novel stepsand practice in producing said sheet all as` hereinafter set forth anddescribed thereupon, and

.be provided with and now particularly pointed out in the Likeletters'refer to like parts throughout the several views.

In the embodiment of the invention shown in the drawings, I employ asheet a of natural cork which owing to its having been sliced from theportionof the cork bark adjacent the outer face of the bark will have anumber of voids a extending entirel therethrough. The number and size ofsuc voids varies in the same and also in di'erent sheets. The closer thecut is to the outer bark, the greater the number and the larger thesevoids will be. This variance will also result from differences in age ofthel cork bark when harvested.

This sheet of cork is backed with a stratum b of composition cork oracompacted body formed of granules of cork, thinly coated with a suitableadhesive or cement. This composition as will hereinafter appear, is in asomewhat plastic condition when it is assembled in the sheet and issubjected to heat and pressure during the assembly op eration, so thatportions b of said backing stratum will extend into and through thevoids va so as to completely fill the same. The portions b exposedthroughsaid voids will be substantially flush with the adjacent surfaceof the sheet a and form therewith a continuous smooth surface formedmainly of natural cork but having small --isolated spots of compositioncorkl varying in size and number throughout the same and difierentsheets.

Between the natural cork sheets a and thev backing stratum b and theportions b and the edges of the voids ai" is a suitable adhesive ccementing said surfacin sheet and esive may appliedto face of thestratum b opposite to that surfaced by the sheet a has a facing ofpaperor other suitable fibrous 'material cemented to said'composition corkstratum by a suitable adhesive h. If desired the facing may gum g in adry state. When this facing g is used it will suffice as a paper colletto facilitate bonding of a disk formed from a sheet embodying my terasseinvention to its metal shell, this collet, how: ever, forming asubstantially integral part of the cushion disk..

this `facing g1 may readily be dispensed with,`

. but is sometimes desirable.

ln the production of a sheet embodying my invention, ll place the sheeta of natural cork in a mold al and deliver to and dis# tributesubstantially equally about said mold, a suiiicient quantity of corkgranules properlycoated with a suitable adhesive to form when compacted,a suitable backing stratum 'h of the desired thickness. lf desired, thestrip a; may be coated on thatv face, With which the cork compositioncontacts, With a suitable adhesive.

Thereafter thermass" of composition cork y is subjected to a compactingpressure, as by a plunger e so as to secure the. desired den' sity andthickness of the stratum formed of said mass, andai: the same timeforce, portions bi'wof this mass into and compact them' Within. anyvoidsa occuring in the sheet While the pressure is thus appliedto thecontents ofthe mold, its contents are subject/ed to heat in anydesiredmanner, as

from the burners f, for an interval sufficient to'set, partially set orproperly condition the adhesive contents of thev matter Within themold., v

rl`he sheet is then removed from the mold., the bottom of Vwhich willhave brought the surface of thesheet ai and the exposed face of anyportion h" substantially Hush, one with vthe other.

The collet forming facing sheet gf may be applied during' the formationof the composite sheet a h c or` subsequently as desired., Cushion disksmado'from a sheet embody-1 l ing my invention may properly be consioh1dit essential characteristics of the arger sheets.. Such sheets are madelarger be ause of economy in production and the absence of dithcultiesin forming, assembling and handling smaller disks separately.

ily producing sheets as described, l am enabled to utilize in very highpercentage of ered as but smaller sheets havigng all of the cork barkfor making satisfactory cushiondisks which otherwise could not be usedfor this purpose. Not only am l enabled' to effect this economy, but llcansecure a very much increased output of cushion disks from a givenquantity of cork bark thus greatly conservinsr cork bark which isproduced in but limited quantities. 'This saving results in part fromthe fact that when a a facing sheetof natural cork only is used,

Withl a backing of composition cork, the natural cork may be of only onequarter or less thicknessI than is required for disks invention When afairly higher grade of cushion disk is to be made. For a lower grade'ofdisk such Waste mixed with Waste frorin sheets embodying the inventionmay be use rlhe present invention is designed to utilize for a facing oncushion disks those portions of natural cork which either from the ageof the bark When'harvested, or from the part of the bark from which thesheet is cut, large voids are inevitable. lf such voids are not presentin a sheet of cork, such a sheet may be advantageously used by othermethods. Hence my present invention permits the utilization ofpractically all of the cork bark for making cushion disks, excepting thehard brittle outer surface. i

Before applying'the backing stratum, to the natural cork sheet, it isdesirable to remove grit or other small particles therefrom by methodscommonly used to clean natural cork when making natural cork disks.

Satisfactory results can be secured by slicing cork bark into sheets ofa thickness of forty or more to the inchinstead of ten to the inch aswhen making natural cork disks, so that l am enabled to secure an outputof disks having all the desirable surface characteristics of naturalcorkat least four times that which can be secured When making natural corkdisks. This saving is augmented by the-condition that the natural corkwhich l utilize by my present invention will amount to more than of thecork bark in' some instances which Would other- Wise have to be dealtwith as Waste.

lt is not my intention to limit the invention to the details shown inthe drawings, since such drawings are merely illustrations of theinvention.

rll`he pressure l emplo ed may vary, although the thickness o thestratum b will permit the desired distribution and compaction of thecoated cork granules by a single application of a fairly light pressureand `Without a tampling -action- Any adhesive now commonly used in thisart may be employed and the temperature during the application ofpressure vvill be determined by the adhesive used and the time intervalrequired to properly condition such adhesive. Having described myinvention, What l claim as new and desire to have protected by LettersPatent is:-.

1 A sheet for making cushion disks con sisting of a surfacing sheet ofnatural cork havingA voids extending therethrough, a

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stratum of composition corky having portions thereof extending throughand filling said voids and having their exposed surfaces substantiallyflush with the adjacent surface. of said natural cork sheet and adhesivebonding said surfacing sheet to Said stratum- 2f A sheet for makingcushion' disks consisting of a surfacing sheet of natural cork of athickness to have the elasticity of natural cork and relatively greaterdexibility than natural cork of greater thickness, and having voidsextending therethrough, a stratum of composition cork having portionsthereof extending through and filling said voids and having theirexposed surfaces substantially flush with the adjacentV surface of saidnatural cork sheet and adhesivegbonding said surfacing sheet to saidstratum.

3- A sheet for making cushion disks consisting of a surfacing sheet ofnatural cork having voids extending therethrough, a stratum ofcomposition `cork having ortions thereof extending through'and fil ingsaid voids and having their exposed surfaces substantially Hush with theadjacent surface of said natural cork sheet, adhesive bonding saidsurfacing sheet to said stratum, and a gummed sheet of collet kform'-ing material bonded to the opposite side thereof.

4. rlihe herein described method. of making a sheet/for making cushiondisks consisting in applying pressure to a distributed and isolatedspots of composition cork, is.

formed. 5. The herein described method of making'a sheet for makingcushion disks consisting in placing a sheet of natural cork ,havingvoids therethrough Within a mold,

coating theexposed surface of said sheet with an adhesive, deliveringand distributing a mass of cork granules coatedwith adhesive within themold upony said sheet, applying compacting pressure to said granuleswhereby portions thereof. will be forced and compacted within the voidsin said sheet, and applying heatl to said mold While the mass therein isheld compacted whereby a unitary sheet having a stratum of compositioncork and a surface formed of natural cork and isolated spots of con1-position cork, is formed.

in witness vvhereoiZ l" have hereunto axed my signature this 24th day ofAugust, 1923.

. CHARLES E. MGMANUS.

